Ergonomics done right.®
May 9th, 2013

MMH Solutions Webinar Q & A

Thank you to those of you who attended yesterday’s webinar on material handling solutions. We had a lot of fun presenting the material and hope you found it worthwhile. There were some great questions that came in and we’ve summarized our responses below. As always, if you have additional ideas or products to share with us, please do!

Q: Aren’t “overuse” injuries (e.g. wrist tendinitis in an office worker) also “overexertion” injuries, and are these included in these stats?­

Great point.  Repetitive motion injuries were also included in Liberty Mutual’s 2012 Workplace Safety Index.  They accounted for about 4% or $2.02 billion of injury costs to companies. 

Q: ­Can the full OHIO website be provided by email, I only got part of it.

The Ohio Bureau of Workers’ Compensation Lifting Guide is another great tool to assess some of the MMH tasks where you work, to make sure that our employees are protected from ergonomic risk.

Q: ­If I push a cart normally, but want to measure the push force w/ a fish scale, I assume I can measure w/ the fish scale pulling and that will also tell me the pushing force? ­

That is right.  We also recommend turning all swiveling casters 90 degrees to simulate the worst case pushing force.  Remember to get at least three measurements to ensure accuracy.

Q: ­For loading water bottles onto water coolers, I’ve seen a powered lift for the bottle but are the simpler solutions to this problem that you’ve seen?­

Remember the ‘comfort zone’.  If possible store the bottles above 24″ (the bottom of the comfort zone).  I have seen companies block the bottom shelf, or raise the entire storage unit above 24″.

Q: ­Where did the Cart Guidelines come from – research?­

We base all of our design guidelines on scientific research.  One resource we used for cart design is “Pushing and Pulling Carts and Two-Wheeled Hand Trucks” by Jung, M., Haight J., Freivalds (2005).

Q: ­do you have a reference for your cart guidelines – load >500lbs   I am assuming the 500 lbs is the load on cart not the cart and load weight­?

You can see the reference above for the publication.500 lb does represent the load on the cart. What we have found is that if you have less than optimal conditions (poor handle design and flooring) then having a load of greater than 500 lb will generally result in a push/pull force above suggested guidelines.  As always, remember it is best to measure that actual push/pull force and compare to such tools as Liberty Mutual Push/Pull tables.

Q: ­The lift and turn tables can be very expensive. Are there specific guidelines for when we need to put one in? Or a way to justify it?­

Cost justification can be made by looking at time savings.  If our employees are not “wasting motion” they are probably saving time, resulting in higher productivity.  There are many tools that can help measure that, one is Humantech’s STEP analysis.  You can also use the NIOSH lifting equation to evaluate the acceptability of the lifting or lowering task.

Q: What are your ­thoughts on back belts?

Back belts do not help eliminate the exposure to the MMH risk.  The solutions that we focus on will help reduce or eliminate one side of the ergonomics ‘fire triangle’ force, frequency, or posture.

Q: ­Who manufactured the three carts you showed (trash dumper, etc.)?­

Powered lift and turn cart – Southworth Products

Six-wheeled electric cart and trash dumper – ERGOdynamics

Q: ­A lot of this seems geared toward a fixed site.  We are a water utility. Our guys are in the street then move on.  Can some of this lift assist stuff be more portable?  ­

Consider a portable work platform dolly.  Our clients have had good success with using the Mule Lift Truck.

Q: ­Groups who work in remote sites often suffer shoulder injuries due to repetitive movements, has there ever been research that speaks to elevator lifts for extended heights > 40 steps for the average 15 gal buckets?­

We aren’t aware of any research addressing this issue specifically for handling 15 gallon buckets.  My gut inclination is that there are probably several issues involved (heart rate, WMDS, trip/fall hazards) in this work task and multiple analyses would be needed to provide a clear picture of the risk to the worker.

Q: ­We use 48 lb motor and orders range from 5 to 50 pieces. What out of the applications you showed today would be recommended from getting these from pallets to workbenches with or without carts?­

Many of the lift assist devices can accomplish this task.  You may have to work with the manufacturer to engineer an appropriate end effector for you specific application. We have had good luck with ball roller tables and stabilizing clamps mounted to hand truck.  The Equipois mobile cart we showed during the webinar seems like a good fit for your needs.  Here is a link to an online summary of the solution, which shows a sample configuration, a video, and rough costs.  

Q:  What are some vendors for pneumatic lift tables?

Southworth Products offers a pneumatic lift table.  The tables can range in capacity, reaching up to 4,000 lb.

Q:  What is the approximate cost of the dolly assister I see on the steps?  How heavy is it?  I’m thinking about lifting it in and out of a truck.

You can find lightweight dollies for between $100 – $200 through suppliers like Northern Tool and Equipment  or find stair climber that bolt on to existing dollies from Uline or Magliner.  There are many other vendors for these products.